The invention generally relates to a system and method for the fixation of fractures in one or more objects, and more particularly, to a lagwire system and related components for the fixation of bone fractures.
It is well-known in the medical arts that constant pressure on a bone fracture speeds healing. As such, orthopedic physicians typically insert one or more screws in the area of the fracture in order to assert constant pressure on the bone fracture. However, the insertion of existing screws through or around fractures has disadvantages. For example, the entire process is very time-consuming because inserting a regular screw usually involves multiple steps such as drilling the pilot hole, measuring the relevant distances to determine the appropriate screw selection, tapping the hole to establish threads and screwing the screw into the hole. Moreover, when using a lagscrew, the process usually includes even more steps such as drilling through the near cortex to establish the gliding hole (e.g., 3.5 mm), placing the drill guide in the proper location, drilling through the far cortex (e.g., 2.5 mm), measuring the distance to determine the appropriate screw selection, tapping the hole to establish threads and screwing the screw into the hole, thereby attempting to compress the fracture. Again, each step and the entire process is very time-consuming.
In addition to the length and complexity of the process, the prior art system also typically includes inadequate components. For example, in poor bone, prior art screws often loose their grip and strip out of the bone. Currently available lag screws also typically provide only one side of cortex fixation and are generally not suited for percutaneus surgery. Moreover, when placing the screws in the bone, the physician may not accurately set the screw into the distal hole or may miss the distal hole completely, thereby resulting in the screw stripping the threads or breaking the bone.
Furthermore, the location and extent of most every fracture is unique, so different screws are often needed for each fracture. Because the physician typically is unable to accurately determine the type or size of screw needed until the physician enters the bone and measures the appropriate screw placement, operating facilities need to store and make available large inventories of screws. Particularly, screws usually range in length from about 10 mm to about 75 mm with available screw sizes limited to every 2 mm there between. Moreover, for each size of screw, the screws may be either a cancellous or cortical type, and for each size and type of screw, the screw may include one of three different pitches. Accordingly, a screw set typically exceeds one hundred screws. Furthermore, if cannulated screws are desired, another entire screw set of over one hundred additional screws is often needed. Moreover, each time a screw from a screw set is utilized in a procedure, a replacement screw is typically obtained to complete the set. As such, inventory management of screws is a very large problem for many operating facilities. A need exists for a lagwire system which simplifies and expedites the process for the fixation of bone fractures, while minimizing the number of components needed in the process.
In general, the invention facilitates the fixation of bone fractures. In a particular embodiment, the head component includes a tip, cutting threads and mating threads which are inserted into the far cortex of the bone. A wire extends from the head component and exits from the near cortex. A cap device having a sawtooth inner surface is threaded over the wire having an inverse sawtooth outer surface such that the cap is restricted from backwards movement. Tension is then applied to the wire while the cap is tightened against or within the bone surface to thereby apply an appropriate amount of pressure between the surfaces of the fracture. The excess wire beyond the cap can then be removed.
The invention also includes a system for facilitating a change in distance between objects, wherein the system includes a head component configured to attach to one of the objects; a wire having a first end and a second end, wherein the first end of the wire is configured to mate with the head component; and, a cap configured to mate with the second end of the wire. The invention also includes a method for facilitating a change in distance between a first and second surface The method includes providing a head component mated with a wire having a first interface component; inserting the head component into the first surface by mating a drill over a driver head of the head component to facilitate drilling the head component into the bone and cutting new threads into the object using the cutting threads and mating the new threads with the mating threads; extending the wire through the second surface; threading a cap having a second interface component over the first interface component of the wire; and removing the excess wire beyond the cap.